Document photosensor of surface-mounted elements

ABSTRACT

A document photosensor is provided which comprises a substrate  11, 12 , a bracket  41, 42  disposed on substrate  11, 12  for forming a light diffusion chamber  53  and a light receiving chamber  58  separated from each other, an LED chip  21, 31  surface-mounted on substrate  11, 12  in light diffusion chamber  53 , and a PD chip  37, 38  surface-mounted on substrate  11, 12  in light receiving chamber  58 . These chips  21, 37, 31  and  38  are secured at precise locations on a substrate  11  and  12  with accuracy on the order of a few micrometers or less to exactly detect by PD chip  37, 38  a light irradiated from LED chip  21  or  31  after reflection of the light on a bill  50  moved along a passageway  55  to improve validation performance of bill  50.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the U.S. Continuation application of Ser. No.12/859,383, filed Aug. 19, 2010, which claims priority of JapaneseApplication No. 2009-190537, filed Aug. 19, 2009.

TECHNICAL FIELD

This invention relates to a document photosensor, in particular ofsurface-mounted elements for detecting a plurality of optical featuresresulted from lights reflected on a document to improve performance ofdocument validation.

BACKGROUND OF THE INVENTION

FIG. 22 shows a prior art bill validator 100 capable of detecting aplurality of optical features of valuable papers or bills by means oflights penetrating or reflected on bills. Validator 100 comprises aconveyer device 102 for transporting a bill 50 inserted into an inlet101 along a passageway 55, a sensor device 110 for detecting optical andmagnetic features of bill 50 traveling along passageway 55, and acontrol device 103 for receiving outputs from sensor device 110 todecide authenticity of bill 50 and also forward drive signals toconveyer device 102. A frame 104 comprises upper and lower casings 104 aand 104 b to accommodate conveyer device 102, sensor device 110 andcontrol device 103 therein.

Not shown in the drawings, however, control device 103 comprises amemory that has previously stored information on patterns of lightamount transmitted through and reflected on bill and magnetic pattern ofbill, and a central processing unit (CPU) for comparing bill informationoutput from sensor device 110 with stored bill information in the memoryto decide kinds of bill 50 and authenticity of bill in accordance withagreement or disagreement between detected and stored information andalso to control drive of conveyer device 102. Sensor device 110comprises an optical sensor 111 for photo-electrically detecting opticalfeatures of bill 50 to produce detection signals and a magnetic sensor112 for magneto-electrically detecting magnetic ink features printed ina predetermined area of bill 50 to produce detection signals. CPU 103compares detection signals received from optical and magnetic sensors111, 112 with stored signals in memory to decide authenticity or falseof bill 50. When detection signals agree with signals in memory, CPU 103decides bill 50 as genuine to further drive conveyer device 102, andbill 50 is further moved through an outlet 106 to stow it in a stackingchamber 105. To the contrary, when detection signals do not agree withsignals in memory, CPU 103 decides bill 50 as false to drive conveyerdevice 102 in the adverse direction, and bill 50 is returned to inlet101. A bill validator of the foregoing type is shown for example in U.S.Pat. No. 7,182,197.

In the bill validator 100 seen in FIG. 23, optical sensor 111 comprisesphotocouplers made up of light emitting diodes 114 and photo-transistors115 deployed in the vicinity of and on the opposite sides of passageway55 and in a vertically spaced relation to each other. Each of lightemitting diodes 114 and photo-transistors 115 has a plastic shell 114 a,115 a and outer leads or pins 117 extended from plastic shell 114 a, 115a to mount them on upper and lower printed circuit boards 116 in frame104 inserting and fastening pins 117 in through-halls on printed circuitboards 116. Each of light emitting diodes 114 and photo-transistors 115has a hemi-spherical lens formed at the tip of plastic shell 114 a, 115a, and cylindrical lenses 118 are disposed opposite to hemi-sphericallenses of plastic shell 114 a, 115 a.

Optical sensor devices of this type are shown in for example U.S. Pat.Nos. 5,381,019; 5,903,339; and 7,242,796; and Japanese Utility ModelRegistration No. 3,037,946.

Such a prior art optical sensor device of the pin-insertion type howeveris disadvantageous because a plurality of light emitting diodes cannotbe mounted in their accurate vertical and horizontal positions onprinted circuit boards due to various or diversified shapes of outerleads or uneven or different attachment positions of outer leads inthrough-holes of printed circuit boards. This results in deviation of alight emission axis of light emitting diodes from a correct optical axisupon attachment on printed circuit boards while impeding an exact andeffective detection of optical features from bills because lightemitting diodes cannot correctly and precisely irradiate lights onpredetermined target points on bill. There is also another defect in theprior art optical sensor device because plastic shell and outer leadsextended from plastic shell cause height and thickness in sensor deviceto undesirably increase. Also, the more number of optical sensingelements is increased to improve detection accuracy of transmitted-lightamount pattern, the more the occupation area of sensor device expands,thereby causing bill validator to be made in inconveniently larger size.Moreover, the prior art sensor device necessarily needs cylindricallenses for light emitting diodes and light receiving transistors inaddition to their hemi-spherical lenses. In this case, error inmanufacture of sensor device would fluctuate light beams from lightemitting diodes, and this may have a bad impact on uniform light beams.In another aspect, the inventors of the present invention firmly believethat one of modern bill validation techniques would pick outmulticolored data of lights penetrated through many microscopic areas ofa bill and then to precisely decide whether differences or rates betweenoptical outputs in different wavelength are within or out of apredetermined range.

Accordingly, an object of the present invention is to provide a documentphotosensor capable of detecting a plurality of optical features of adocument for improvement in detection performance of light amountpatterns reflected on the document. Another object of the presentinvention is to provide a document photosensor that has less number oflight receiving elements capable of receiving lights of differentwavelength irradiated from increased number of light emitting elementsfor improvement in validation performance. Still another object of thepresent invention is to provide a document photosensor in small sizethat comprises light emitting and receiving elements disposed at areduced interval therebetween with the light emitting elements alsodisposed at a reduced interval therebetween for detecting a plurality ofoptical features of the document.

SUMMARY OF THE INVENTION

The document photosensor of two optical elements according to thepresent invention comprises: a substrate (11, 12), a bracket (41, 42)disposed on substrate (11, 12) for forming a light diffusion chamber(53) and a light receiving chamber (58) separated from each other, alight emitting element (21, 31) surface-mounted on substrate (11, 12) inlight diffusion chamber (53), and a light receiving element (37, 38)surface-mounted on substrate (11, 12) in light receiving chamber (58).Light emitting element (21, 22) is turned on to irradiate a light thatradiates and spreads in light diffusion chamber (53).

The document photosensor of two optical elements can improve detectionperformance of light amount pattern permeated through a document asfollows:

[1-1] In manufacture of the document photosensor, mounters may be usedto sack and hold under vacuum light emitting element (21, 31), toprecisely mount it at a predetermined surface location on substrate (11,12) with accuracy on the order of a few micrometers or less to exactlydetect a light reflected on document (50) by light receiving element(37, 38).

[1-2] Light emitting element (21, 31) is a light emitting diode chipsurface-mounted on substrate (11, 12) to notably and more reducethickness and array length of a sensor assembly (1, 2) compared to theprior art structure by pin-insertion technique.

[1-3] Light emitting element (21, 31) is directly secured on substrate(11, 12) without error or deviation in mounting of the element whileexactly aligning a light axis of light emitting element (21, 31) unlikethe prior art structure by pin-insertion technique.

The document photosensor of three optical elements according to thepresent invention comprises: a substrate (11, 12), a bracket (41, 42)disposed on substrate (11, 12) for forming a light diffusion chamber(53) and a light receiving chamber (58) separately from each other,first and second light emitting elements (21, 22, 31, 32)surface-mounted on substrate (11, 12) in light diffusion chamber (53),and a light receiving element (37, 38) surface-mounted on substrate (11,12) in light receiving chamber (58).

The document photosensor of three optical elements can improve detectionperformance of light amount pattern permeated through a document asfollows:

[2-1] In manufacture of the document photosensor, mounters may be usedto sack and hold under vacuum first and second light emitting elements(21, 22, 31, 32), to precisely mount them at given surface locations onsubstrate (11, 12) with accuracy on the order of a few micrometers orless to exactly detect lights reflected on document 50 by lightreceiving elements (37, 38).

[2-2] Adjoining first and second light emitting elements (21, 22, 31,32) may be surface-mounted on upper substrate (11) in a spaced distanceor with pitch less than 1 mm, preferably less than 0.6 mm. Accordingly,first and second light emitting elements (21, 22, 31, 32) irradiatelights that are reflected on document (50) and then are received bylight receiving element (37, 38) while improving detection accuracy inlight amount pattern reflected on document (50). However, one ofordinary skill in the art may select different pitch distances betweenlight emitting elements as necessary in view of size of light emittingelements and insulation requirements.

[2-3] All of first and second light emitting elements (21, 22, 31, 32)are light emitting diode chips surface-mounted on substrate (11, 12) tonotably and more reduce thickness and array length of sensor assemblies(1, 2) compared to the prior art structure by pin-insertion technique.

[2-4] First and second light emitting elements (21, 22, 31, 32) aredirectly secured on substrate (11, 12) without error or deviation inmounting of the elements while exactly aligning each light axis of firstand second light emitting elements (21, 22, 31, 32) unlike the prior artstructure by pin-insertion technique.

[2-5] The document photosensor may comprise increased number of lightemitting elements for irradiating lights of different wavelength todetect increased number of light amount patterns reflected on document(50) for more improvement in validation performance while reducingnumber of light receiving elements for reduction in cost for manufacturecompared to the prior art optical sensor.

The document photosensor of four optical elements according to thepresent invention comprises: a substrate (11, 12), a bracket (41, 42)disposed on substrate (11, 12) for forming a light diffusion chamber(53) and a light receiving chamber (58) separately from each other,first, second and third light emitting elements (21, 22, 23, 31, 32, 33)surface-mounted on substrate (11, 12) in light diffusion chamber (53),and a light receiving element (37, 38) surface-mounted on substrate (11,12) in light receiving chamber (58).

The document photosensor of four optical elements can improve detectionperformance of light amount pattern reflected on a document as follows:

[3-1] In manufacture of the document photosensor, mounters may be usedto sack and hold under vacuum first to third light emitting elements (21to 23, 31 to 33) to precisely mount them at predetermined surfacelocations on substrate (11, 12) with accuracy on the order of a fewmicrometers or less to exactly detect lights reflected on document 50 bylight receiving element (37, 38).

[3-2] Adjoining first and second light emitting elements (21 to 23, 31to 33) may be surface-mounted on upper substrate (11) in a spaceddistance or with pitch less than 1 mm, preferably less than 0.6 mm.Accordingly, adjoining first to third light emitting elements (21 to 23,31 to 33) irradiate lights that are reflected on document (50) and thenare received by light receiving element (37, 38) while improvingdetection accuracy in light amount pattern reflected on document (50).

[3-3] All of first to third light emitting elements (21 to 23, 31 to 33)are light emitting diode chips surface-mounted on substrate (11, 12) tonotably and more reduce thickness and array length of a sensor assembly(1, 2) compared to the prior art structure by pin-insertion technique.

[3-4] First to third light emitting elements (21 to 23, 31 to 33) aredirectly secured on respectively substrate (11, 12) without error ordeviation in mounting of the elements while exactly aligning each lightaxis of first to third light emitting elements (21 to 23, 31 to 33)unlike the prior art structure by pin-insertion technique.

[3-5] The document photosensor may comprise increased number of lightemitting elements for irradiating lights of different wavelength todetect increased number of light amount patterns reflected on document(50) for more improvement in validation performance while reducingnumber of light receiving elements for reduction in cost for manufacturecompared to prior art optical sensor.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other objects and advantages of the presentinvention will be apparent from the following description in connectionwith preferred embodiments shown in the accompanying drawings wherein:

FIG. 1 is a longitudinal section view of a first embodiment of thedocument photosensor with four optical elements according to the presentinvention;

FIG. 2 is a transverse section view of the first embodiment shown inFIG. 1;

FIG. 3 is a longitudinal section view of a second embodiment of thedocument photosensor with four optical elements according to the presentinvention;

FIG. 4 is a transverse section view of the second embodiment shown inFIG. 3;

FIG. 5 is a longitudinal section view of a first embodiment of thedocument photosensor with six optical elements according to the presentinvention;

FIG. 6 is a longitudinal section view of a second embodiment of thedocument photosensor with six optical elements according to the presentinvention;

FIG. 7 is a longitudinal section view of a third embodiment of thedocument photosensor with six optical elements according to the presentinvention;

FIG. 8 is a longitudinal section view of a first embodiment of thedocument photosensor with eight optical elements according to thepresent invention;

FIG. 9 is a longitudinal section view of a second embodiment of thedocument photosensor with eight optical elements according to thepresent invention;

FIG. 10 is a longitudinal section view of a third embodiment of thedocument photosensor with eight optical elements according to thepresent invention;

FIG. 11 is a longitudinal section view of a first embodiment of thedocument photosensor with ten optical elements according to the presentinvention;

FIG. 12 is a longitudinal section view of a second embodiment of thedocument photosensor with ten optical elements according to the presentinvention;

FIG. 13 is a partial perspective view showing a typical arrangement ofLED and PD chips mounted on a substrate for use in the presentinvention;

FIG. 14 is a partial perspective view showing a typical arrangement oflight emitting and receiving elements mounted on a substrate for use inthe present invention;

FIG. 15 is a partially enlarged perspective view of a typicalarrangement of light emitting and receiving elements mounted on asubstrate for use in the present invention;

FIG. 16 is a perspective view showing a variation of an aspheric lens;

FIG. 17 is a longitudinal section view showing an embodiment of thedocument photosensor according to the present invention comprising fiveoptical sensor devices each having four optical elements;

FIG. 18 is a longitudinal section view showing an embodiment of thedocument photosensor according to the present invention comprising fiveoptical sensor devices each having six optical elements;

FIG. 19 is a longitudinal section view showing an embodiment of thedocument photosensor according to the present invention comprising fiveoptical sensor devices each having eight optical elements;

FIG. 20 is a longitudinal section view showing an embodiment of thedocument photosensor according to the present invention comprising fiveoptical sensor devices each having ten optical elements;

FIG. 21 is a longitudinal section view showing an embodiment of thedocument photosensor according to the present invention comprising fiveoptical sensor devices having respectively four, six, eight and tenoptical elements;

FIG. 22 is a section view of a prior art bill validator;

FIG. 23 is a section view of a prior art optical sensing device.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the document photosensor according to the presentinvention applied to bill validators will be described hereinafter inconnection with FIGS. 1 to 21 of the drawings. Same reference symbols asthose shown in FIGS. 22 and 23 are applied to similar portions in FIGS.1 to 21, omitting explanation thereon. Shown coordinate axes X, Y and Zindicate respectively a transverse or lateral direction of passageway 55or document 50 traveled through passageway 55; a vertical directionalong a height of document 50; and a longitudinal or lengthwisedirection along a length of document 50 or moved direction of document50 through passageway 55. A word “document” herein means a valuablepaper, a bill, currency, security, coupon, tender, scrip or all othervaluable document. A phrase “top” or “upper portion” herein means anupper position along Y axis, and a phrase “bottom” or “lower potion”herein means a lower position along Y axis. An upper X axis upward alongY axis means a first array line 56 along which light emitting andreceiving elements shown in FIG. 14 are mounted, and a lower X axisdownward along Y axis means a second array line 57. First and secondarray lines 56 and 57 are in parallel to each other and perpendicular tothe lengthwise direction of passageway 55. A wording “aspheric lens”herein is used to condense a light irradiated from a light emittingelement in a transverse line toward bill to irradiate a linear lightbeam on bill, and also to condense the linear light beam on bill towarda light receiving element. To this end, such an aspheric lens isselected from cylindrical lens, partly cylindrical lens, parabolic lensor similar or equivalent lens. Finally, a bracket is used to maintain anaspheric lens in position and to prevent inward incidence of externaldisturbing light.

FIGS. 1 to 4 illustrate document photosensors 10 a and 10 b of fouroptical elements according to the present invention. Photosensor 10 ashown in FIGS. 1 and 2 comprises an upper sensor assembly 1 disposed onan upper side of a passageway 55 along which a bill 50 is transportedand a lower sensor assembly 2 disposed on the opposite lower side ofpassageway 55 from upper sensor assembly 1. Upper sensor assembly 1comprises an upper base plate 13 having a plurality of upper terminals63 formed on upper base plate 13, an upper substrate 11 mounted on upperbase plate 13 and having a plurality of upper conductive leads 61electrically connected to a plurality of upper terminals 63 formed onupper base plate 13, an upper LED (light emitting diode) chip 21 as anupper light emitting element surface-mounted on upper substrate 11 andhaving a pair of terminals electrically connected to related ones ofupper conductive leads 61, and an upper PD (photo-diode) chip 37 as anupper light receiving element surface-mounted on upper substrate 11 andhaving a pair of terminals electrically connected to related ones ofupper conductive leads 61, an upper bracket 41 disposed on uppersubstrate 11, and an upper aspheric lens 51 supported on upper bracket41 opposite to upper LED and PD chips 21 and 37.

As seen in FIG. 13, upper LED chip 21 has one terminal secured on andelectrically connected to an upper emission electrode 71 formed on uppersubstrate 11; upper emission electrode 71 is electrically connected toone of upper conductive leads 61; the other terminal of upper LED chip21 is electrically connected to another upper lead 61 via a golden wire.Upper PD chip 37 has one terminal secured on and electrically connectedto an upper acceptance electrode 81 formed on upper substrate 11; upperacceptance electrode 81 is electrically connected to one of upperconductive leads 61; the other terminal of upper PD chip 37 iselectrically connected to still another upper lead 61 via a golden wire.Upper emission and acceptance electrodes 71 and 81 are in alignment withfirst array line 56 normal to the longitudinal direction of passageway55. A plurality of upper leads 61 on upper substrate 11 are electricallyconnected to upper terminals 63 on upper base plate 13 by solder ormetallic binding material. Upper aspheric lens 51 is secured on an upperbracket 41 opposite to upper LED and PD chips 21 and 37 which are fedelectric power through upper leads 61.

Similarly to upper sensor assembly 1, lower sensor assembly 2 comprisesa lower base plate 14 having a plurality of lower terminals 64 formed onlower base plate 14, a lower substrate 12 mounted on lower base plate 14and having a plurality of lower conductive leads 62 electricallyconnected to a plurality of lower terminals 64 formed on lower baseplate 14, a lower LED (light emitting diode) chip 31 as a lower lightemitting element surface-mounted on lower substrate 12 and having a pairof terminals electrically connected to related ones of lower conductiveleads 62, and a lower PD (photo-diode) chip 38 as a lower lightreceiving element surface-mounted on lower substrate 12 and having apair of terminals electrically connected to related ones of lowerconductive leads 62, a lower bracket 42 disposed on lower substrate 12,and a lower aspheric lens 52 supported on lower bracket 42 opposite tolower LED and PD chips 31 and 38.

As shown in FIG. 13, lower LED chip 31 has one terminal secured on andelectrically connected to a lower emission electrode 72 formed on lowersubstrate 12; lower emission electrode 72 is electrically connected toone of lower conductive leads 62; the other terminal of lower LED chip31 is electrically connected to another lower lead 62 via a golden wire.Lower PD chip 38 has one terminal secured on and electrically connectedto a lower acceptance electrode 82 formed on lower substrate 12; loweracceptance electrode 82 is electrically connected to one of lowerconductive leads 62; the other terminal of lower PD chip 38 iselectrically connected to still another lower lead 62 via a golden wire.Lower emission and acceptance electrodes 72 and 82 are in alignment withsecond array line 57 normal to the longitudinal direction of passageway55. A plurality of lower leads 62 on lower substrate 12 are electricallyconnected to lower terminals 64 on lower base plate 14 by solder ormetallic binding material. Lower aspheric lens 52 is secured on a lowerbracket 42 opposite to lower LED and PD chips 31 and 38 which are fedelectric power through lower leads 62.

Upper and lower aspheric lenses 51 and 52 serve to respectively convertlights irradiated from upper and lower LED chips 21 and 32 into parallellinear light beams. Upper aspheric lens 51 also functions to focus ontoupper PD chip 37 light irradiated from lower LED chip 31 and thenpenetrated through bill 50, and in a similar manner, lower aspheric lens52 works to focus on to lower PD chip 38 light irradiated from upper LEDchip 21 and penetrated through bill 50. Accordingly, upper and lowerlight emitting elements 21 and 31 do not require to have their inherentunitized lens.

Upper and lower base plates 13 and 14 are secured to respectively upperand lower walls 55 a and 55 b to define a passageway 55 in frame 104.Upper and lower brackets 41 and 42 comprise respectively upper and lowerpartitions 43 and 44 for isolating upper LED and PD chips 21 and 37, andlower LED and PD chips 31 and 38. Formed in upper and lower substrate 11and 12 are respectively upper and lower openings 11 a and 12 a in whicheach end of upper and lower partitions 43 and 44 is fit for secureattachment of upper and lower brackets 41 and 42 in position.

An upper aspheric lens 51 is disposed on upper partition 43 in a spacedrelation by a certain distance to upper LED and PD chips 21 and 37, anda lower aspheric lens 52 is disposed on lower partition 44 in a spacedrelation by a certain distance to lower LED and PD chips 31 and 38.Upper partition 43 of upper bracket 41 serves to block direct incidenceof light from upper LED chip 21 into upper PD chip 37 adjacent to upperLED chip 21 to prevent pseudo-lighting or malfunction of upper PD chip37. Alike, lower partition 44 of lower bracket 42 serves to block directincidence of light from lower LED chip 31 into lower PD chip 38 adjacentto lower LED chip 31 to prevent malfunction of lower PD chip 38.

In document photosensor 10 a shown in FIGS. 1 and 2, upper and lower LEDchips 21 and 31 are symmetrically disposed about a central point inpassageway 55, and also, upper and lower PD chips 37 and 38 aresymmetrically disposed. Upper and lower LED chips 21 and 31 are turnedon at different points in time under time division control to preventsimultaneous reception of lights from upper and lower LED chips 21 and31 by upper and lower PD chips 37 and 38.

Light irradiated from lower LED chip 31 is converted through loweraspheric lens 52 into parallel linear light beams which penetrate bill50 and then are gathered on upper PD chip 37 through upper aspheric lens51 to receive gathered beams by upper PD chip 37. Likewise, lightirradiated from upper LED chip 21 is converted through upper asphericlens 51 into parallel linear light beams which penetrate bill 50 andthen are gathered on lower PD chip 38 through lower aspheric lens 52 toreceive gathered beams by lower PD chip 38. In this case, after upperLED chip 21 is turned off, lower LED chip 31 is turned on, and afterlower LED chip 31 is turned off, upper LED chip 21 is turned on.

In document photosensor 10 b shown in FIGS. 3 and 4, upper and lower LEDchips 21 and 31 and upper and lower PD chips 37 and 38 are symmetricallydisposed about a transversely central axis across passageway 55. In thedocument photosensors with four optical elements shown in FIGS. 1 to 4,upper and lower LED chips 21 and 31 may irradiate lights of differentwavelength to produce light data of two kinds transmitted through bill50 for decision of bill validity.

FIGS. 5 to 7 show the document photosensors 10 c, 10 d, 10 e of sixoptical elements according to the present invention. As is apparent fromFIG. 5, the document photosensor 10 c comprises an upper sensor assembly1 disposed on one side of passageway 55 along which document 50 istransported and a lower sensor assembly 2 disposed on the opposite sideof passageway 55 from upper sensor assembly 1.

Upper sensor assembly (1) comprises an upper base plate 13 having aplurality of upper terminals 63, an upper substrate 11 secured on upperbase plate 13 and having a plurality of upper conductive leads 61electrically connected to corresponding upper terminals 63 on upper baseplate 13, first and second upper LED chips (first and second upper lightemitting elements) 21, 22 individually surface-mounted on uppersubstrate 11 and having a pair of terminals electrically connected torelated ones of upper conductive leads 61, an upper PD chip (upper lightreceiving element) 37 surface-mounted on upper substrate 11 and having apair of terminals electrically connected to related ones of upperconductive leads 61, an upper bracket 41 disposed on upper substrate 11,and an upper aspheric lens 51 supported on upper bracket 41.

As seen in FIG. 13, first and second upper LED chips 21, 22 each haveone terminal separately secured on and electrically connected to upperdiscrete emission electrode 71 formed on upper substrate 11; each upperemission electrode 71 is connected to one of upper leads 61; and eachthe other terminal of first and second upper LED chips 21 and 22 isindividually electrically connected to another lead 61 through goldenwire. One terminal of upper PD chip 37 is secured on and electricallyconnected to upper receipt electrode 81 formed on upper substrate 11;upper receipt electrode 81 is connected to another one of upper leads61; the other terminal of upper PD chip 37 is electrically connected toanother one of upper leads 61 through golden wire. Upper emission andreceipt electrodes 71 and 82 are disposed in alignment with first arrayline 56 perpendicular to the longitudinal direction of passageway 55. Aplurality of upper leads 61 on upper substrate 11 are electricallyconnected to upper terminals 63 on upper base plate 13 through solder ormetallic adhesive to feed electric power to first and second upper LEDchips 21, 22 and upper PD chip 37 through upper leads 61. Aspheric lens51 is fixed within upper bracket 41 opposite to first and second upperLED chips 21, 22 and upper PD chip 37.

Similarly to upper sensor assembly 1, lower sensor assembly 2 comprisesa lower base plate 14 formed with plurality of lower terminals 64, firstand second lower LED chips (first and second lower light emittingelements) 31, 32 each having two terminals electrically connected to aplurality of lower leads 62 electrically connected to correspondinglower terminals 64 on lower base plate 14, a lower PD chip (lower lightreceiving element) 38 surface-mounted on lower base plate 12 and havingtwo terminals electrically connected to corresponding lower leads 62, alower bracket 42 attached on lower substrate 12, and an aspheric lens 52supported on lower bracket 42.

As shown in FIG. 13, each one terminal of first and second lower LEDchips 31, 32 is secured on and electrically connected to discrete loweremission electrode 72 formed on lower substrate 12; each lower emissionelectrode 72 is connected to one of lower leads 62; each the otherterminal of first and second lower LED chips 31, 32 is individuallyelectrically connected to another lower lead 62 through golden wire. Oneterminal of lower PD chip 38 is secured on and electrically connected tolower acceptance electrode 82 formed on lower substrate 12; loweracceptance electrode 82 is connected to another one of lower leads 62;and the other terminal of lower PD chip 38 is connected to another oneof lower leads 62 through golden wire. Lower emission and acceptanceelectrodes 72 and 82 are disposed in alignment with a second array line57 perpendicular to the longitudinal direction of passageway 55. Aplurality of lower leads 62 on lower substrate 12 are electricallyconnected to lower terminals 64 on lower base plate 14 through solder ormetallic adhesive to supply electric power to first and second lower LEDchips 31, 32 and lower PD chip 38 through lower leads 62. A loweraspheric lens 52 is fixed within lower bracket 42 opposite to first andsecond lower LED chips 31, 32 and lower PD chip 38.

Lower PD chip 38 receives lights irradiated from first and second upperLED chips 21, 22 and then penetrating bill 50, and a second length alongsecond array line 57 of an acceptance surface in lower PD chip 38 isequal to or greater than a length along first array line 56 of anemission surface in upper LED chips 21, 22. Upper PD chip 37 receiveslights irradiated from first and second lower LED chips 31, 32 and thenpenetrates bill 50, and a first length along first array line 56 of anacceptance surface in upper PD chip 37 is equal to or greater than alength along second array line 57 of an emission surface in lower LEDchips 31, 32. Accordingly, upper and lower PD chips 37 and 38 may eachreceive a full amount of light penetrated through bill 50. Each of firstand second lengths along respectively first and second array lines 56and 57 is 1.5 mm or less.

Document photosensors 10 c, 10 d and 10 e of six optical elements shownin FIGS. 5 to 7 have upper and lower aspheric lenses 51 and 52 that havethe same structure and operation as those in document photosensors 10 aand 10 b of four optical elements shown in FIGS. 1 to 4. However, upperand lower aspheric lenses 51 and 52 may each respectively convert lightsfrom first and second upper and lower upper and lower LED chips 21, 22and 31, 32 into linear light beams of generally rectangular or ellipsesection; these linear light beams have the longitudinal size in thetransverse direction of passageway 55 longer than thickness size in thelongitudinal direction of passageway 55; the longitudinal size of theselight beams is longer than that in photosensors 10 a and 10 b of fouroptical elements in FIGS. 1 to 4; lower and upper PD chips 38 and 37 maydetect respectively lights irradiated from adjoining first and secondupper LED chips 21, 22 and from adjoining first and second lower LEDchips 31, 32 and then penetrated through generally the same areas ormostly overlapped areas in bill 50. In other words, upper and loweraspheric lenses 51 and 52 may convert longer lights respectively alongand from first and second upper LED chips 21, 22 and along and fromfirst and second lower LED chips 31, 32 into parallel linear light beamswhile upper and lower aspheric lenses 51, 52 condense respectivelylights from first and second lower LED chips 31, 32 and from first andsecond upper LED chips 21, 22 all through bill 50 onto upper and lowerPD chips 37 and 38. No inherent unitized lens is required in first andsecond upper and lower light emitting elements 21, 22, 31 and 32.

Lights emitted from first and second lower LED chips 31, 32 areconverted into a parallel linear light beam and projected onto bill 50through lower aspheric lens 52. Light passed through bill 50 is gatheredonto upper PD chip 37 through upper aspheric lens 51. Lights emittedfrom first and second upper LED chips 21, 22 are converted into aparallel linear light beam and projected onto bill 50 through upperaspheric lens 51. Light passed through bill 50 is focused onto lower PDchip 38 through lower aspheric lens 52. After turning first upper LEDchip 21 off, second upper LED chip 22 is turned on to receive light fromsecond upper LED chip 22 through bill 50 by lower PD chip 38. Likewise,after turning second upper LED chip 22 off, first lower LED chip 31 isturned on to receive light from lower LED chip 31 through bill 50 byupper PD chip 37. After turning first lower LED chip 31 off, secondlower LED chip 32 is turned on to receive light from second lower LEDchip 32 through bill 50 by upper PD chip 37. After turning second lowerLED chip 32 off, first upper LED chip 21 is turned on to receive lightfrom first upper LED chip 21 through bill 50 by lower PD chip 38.

In document photosensor 10 c, 10 d, 10 e with six optical elements shownin FIGS. 5 to 7, upper and lower base plates 13 and 14 are secured onrespectively upper and lower walls 55 a, 55 b to define passageway 55within frame 104. Upper and lower brackets 41 and 42 compriserespectively upper and lower partitions 43 and 44 for isolating upperLED and PD chips 21 and 37, and lower LED and PD chips 31 and 38. Formedin upper and lower substrate 11 and 12 are respectively upper and loweropenings 11 a and 12 a in which each end of upper and lower partitions43 and 44 is fit for secure attachment of upper and lower brackets 41and 42 in position.

In document photosensor 10 c, 10 d, 10 e with six optical elements shownin FIGS. 5 to 7, an upper aspheric lens 51 is disposed on upperpartition 43 in a spaced relation by a certain distance to upper firstand second LED and PD chips 21, 22 and 37, and a lower aspheric lens 52is disposed on lower partition 44 in a spaced relation by a certaindistance to lower first and second LED and PD chips 31, 32 and 38. Upperpartition 43 of upper bracket 41 serves to block direct incidence oflight from upper first and second LED chips 21, 22 into upper PD chip 37adjacent to upper first and second LED chips 21, 22 to preventpseudo-lighting or malfunction of upper PD chip 37. Alike, lowerpartition 44 of lower bracket 42 serves to block direct incidence oflight from lower first and second LED chips 31, 32 into lower PD chip 38adjacent to lower first and second LED chips 31, 32 to preventmalfunction of lower PD chip 38.

In document photosensor 10 c shown in FIG. 5, upper and lower first LEDchips 21 and 31, upper and lower second LED chips 22 and 32 and upperand lower PD chips 37 and 38 are symmetrically disposed about atransversely central axis across passageway 55. Upper and lower firstand second LED chips 21, 22, 32 and 32 may be turned on at differentpoints in time under time division control to prevent simultaneousreception of lights from upper and lower first and second LED chips 21,22, 31 and 32 by upper and lower PD chips 37 and 38.

Document photosensor 10 d shown in FIG. 6, has first upper and lower LEDchips 21, 31, second upper and lower LED chips 22, 32 and upper andlower PD chips 37, 38 symmetrically disposed about a central pointwithin passageway 55. Document photosensor 10 d shown in FIG. 6 isdifferent from that in FIG. 5 to adjacently deploy first and secondupper LED chips 21 and 22 and first and second lower LED chips 31 and32. Document photosensor 10 e shown in FIG. 7, has first upper andsecond lower LED chips 21 and 32, second upper and first lower LED chips22 and 31 and upper and lower PD chips 37 and 38 symmetrically disposedabout a transverse central axis across passageway 55. In documentphotosensors 10 d and 10 e shown in FIGS. 6 and 7, adjoining first andsecond upper LED chips 21 and 22 and adjoining first and second lowerLED chips 31 and 32 may be surface-mounted on upper and lower substrates11 and 12 in a spaced distance or with pitch less than 0.6 mm,preferably less than 0.45 mm.

In document photosensors 10 c, 10 e, 10 e shown in FIGS. 5 to 7, firstand second upper LED chips 21, 22, first and second lower LED chips 31,32 may produce lights of different wavelength that penetrate bill 50 andthen are detected by upper and lower PD chips 37 and 38 so that acontrol device (not shown) connected to upper and lower PD chips 37 and38 may prepare four kinds of transmitted light pattern data and validateauthenticity of bill 50 by comparing detected four kinds of lightpattern data with reference pattern data or benchmarks previously storedin control device.

In document photosensors 10 c, 10 d shown in FIGS. 5 and 6, first upperand lower LED chips 21, 31 may be symmetrically located about a point toproduce lights of same wavelength, and second upper and lower LED chips22, 32 may be symmetrically located about a point to produce light ofsame wavelength to pick out same transmitted light pattern dataindependently of right side up or bottom side up insertion of bill 50into inlet 101 of bill validator because lights of same wavelengthpenetrate and scan substantially the same positions in bill 50 fromupside or downside in a mirror image. For example, for a baseline levelin authenticity decision of bill 50, control device may decide bill 50as genuine when the resultant light data patterns fulfill the followingrequirements:

1. Each ratio of received and added light amount from first and secondupper LED chips 21, 22 to received light amount from first or secondupper LED chip 21 or 22 is within a predetermined range, and

2. Each ratio of received and added light amount from first and secondlower LED chips 31, 32 to received light amount from first or secondlower LED chip 31 or 32 is within a predetermined range.

FIGS. 8 to 10 illustrate document photosensors 10 f, 10 g, 10 h witheight optical elements according to the present invention. Showndocument photosensor 10 f comprises an upper sensor assembly 1 disposedon one side of passageway 55 for guiding document 50, and a lower sensorassembly 2 disposed on the opposite side of passageway 55 from uppersensor assembly 1. Shown upper sensor assembly 1 comprises an upper baseplate 13 formed with a plurality of terminals 63, an upper substrate 11disposed on upper base plate 13 and having a plurality of upperconductive leads 61, first to third upper LED chips (first to thirdupper light emitting elements) 21 to 23 individually surface-mounted onupper substrate 11 and each having a pair of terminals electricallyconnected to related ones of upper conductive leads 61, and an upper PDchip (upper light receiving element) 37 surface-mounted on uppersubstrate 11 and having a pair of terminals electrically connected torelated ones of upper conductive leads 61, an upper bracket 41 disposedon upper substrate 11, and an upper aspheric lens 51 supported by upperbracket 41.

As shown in FIG. 13, each of first to third upper LED chips 21 to 23 hasone terminal secured on discrete upper emission electrodes 71 formed onupper substrate 11 and connected to different upper conductive leads 61,and each the other terminal of first to third upper LED chips 21 to 23is electrically connected to another lead 61 through golden wire. UpperPD chip 37 has one terminal secured on and electrically connected toupper acceptance electrode 81 formed on upper substrate 11, andconnected to one of upper connective leads 61, and the other terminal ofupper PD chip 37 is electrically connected to another upper lead 61through golden wire. Upper emission and acceptance electrodes 71, 81 aredeployed in alignment along first array line 56 perpendicular to themoved direction of document in passageway 55. A plurality of upper leads61 on upper substrate 11 are electrically connected to upper terminals63 on upper base plate 13 by solder or brazing metal to feed electricpower to first to third upper LED chips 21 to 23 and upper PD chip 37through upper leads 61. Upper aspheric lens 51 is secured within upperbracket 41 opposite to first to third upper LED chips 21 to 23 and upperPD chip 37.

As shown in FIGS. 8 to 10, similarly to upper sensor assembly 1, lowersensor assembly 2 comprises a lower base plate 14 having a plurality oflower terminals 64, a lower substrate 12 disposed on lower base plate 14and having a plurality of lower leads 62, first to third lower LED chips(first to third lower light emitting elements) 31, 32 and 33individually surface-mounted on lower substrate 12 and each having twoterminals electrically connected to lower leads 62, a lower PD chip(lower light receiving element) 38 surface-mounted on lower substrate(12) and having two terminals electrically connected to lower leads 62,a lower bracket 42 disposed on lower substrate 12, and a lower asphericlens 52 supported by lower bracket 42.

As shown in FIG. 13, first to third lower LED chips 31, 32 and 33 eachhave one terminal secured on and electrically connected to discretelower emission electrode 72 formed on lower substrate 12, each loweremission electrode 72 is connected to one of lower leads 62, each theother terminal of first to third lower LED chips 31, 32 and 33 areelectrically connected to different lower lead 62 through golden wire.Lower PD chip 38 has one terminal secured on and electrically connectedto lower emission electrode 82 formed on lower substrate 12, and loweremission electrode 82 is connected to another one of lower leads 62, theother terminal of lower PD chip 38 is connected to another one of lowerleads 62 through golden wire. Lower emission and acceptance electrodes72 and 82 are disposed in alignment with second array line 52perpendicular to longitudinal direction of passageway 55. A plurality oflower leads 62 on lower substrate 12 are electrically connected to lowerterminal 64 on lower base plate 14 through solder or brazing metal toseparately provide electric power to first to third lower LED chips 31,32 and 33 and lower PD chip 38. Lower aspheric lens 52 is secured withinlower bracket 42 opposite to first to third lower LED chips 31, 32 and33 and lower PD chip 38.

In document photosensors with eight optical elements shown in FIGS. 8 to10, upper aspheric lens 51 is disposed on upper partition 43 in a spacedrelation by a certain distance to first to third upper LED chips 21 to23 and upper PD chip 37, and lower aspheric lens 52 is disposed on lowerpartition 44 in a spaced relation by a certain distance to first tothird lower LED chips 31 to 33 and lower PD chip 38. Upper partition 43of upper bracket 41 serves to block direct incidence of light from firstto third upper LED chips 21 to 23 into upper PD chip 37 adjacent tofirst to third upper LED chips 21 to 23 to prevent pseudo-lighting ormalfunction of upper PD chip 37. Alike, lower partition 44 of lowerbracket 42 serves to block direct incidence of light from first to thirdlower LED chips 31 to 33 into lower PD chip 38 adjacent to first tothird lower LED chips 31 to 33 to prevent pseudo-lighting of lower PDchip 38.

Lower PD chip 38 has the acceptance surface whose length along secondarray line 57 is equal to or greater than a length along first arrayline 56 of an emission surface in first to third upper LED chips 21 to23. Likewise, upper PD chip 37 has the acceptance surface whose lengthalong first array line 56 is equal to or greater than a length alongsecond array line 57 of an emission surface in first to third lower LEDchips 31 to 33. This structure ensures receipt of full amount of lightspenetrated through bill 50 by upper and lower PD chips 37 and 38. Forinstance, each length along first and second array lines 56, 57 ofrespective acceptance surface in upper and lower PD chips 37, 38 may beequal to or less than 1.5 mm.

Upper and lower aspheric lenses 51 and 52 in document photosensors 10 f,10 g, 10 h with eight optical elements shown in FIGS. 8 to 10 havesimilar structure and equivalent function or performance to those indocument photosensors 10 c, 10 d, 10 e with six optical elements shownin FIGS. 5 to 7. However, upper and lower aspheric lenses 51 and 52shown in FIGS. 8 to 10 may each respectively convert lights from firstand second upper and lower upper and lower LED chips 21 to 23 and 31 to33 into linear light beams of generally rectangular or ellipse section;these linear light beams have the longitudinal size in the transversedirection of passageway 55 longer than thickness size in thelongitudinal direction of passageway 55; the longitudinal size of theselight beams is longer than that in photosensors 10 c, 10 d and 10 e ofsix optical elements in FIGS. 5 to 7; lower and upper PD chips 38 and 37may detect respectively lights irradiated from adjoining first to thirdupper LED chips 21 to 23 and from adjoining first to third lower LEDchips 31 to 33 and then penetrated through generally the same areas ormostly overlapped areas in bill 50. In other words, upper and loweraspheric lenses 51 and 52 may convert longer lights respectively alongand from first to third upper LED chips 21 to 23 and along and fromfirst to third lower LED chips 31 to 33 into parallel linear light beamswhile upper and lower aspheric lenses 51, 52 condense respectivelylights from first to third lower LED chips 31 to 33 and from first tothird upper LED chips 21 to 23 all through bill 50 onto upper and lowerPD chips 37 and 38. No inherent unitized lens is required in first tothird upper and lower light emitting elements 21 to 23, 31, 32 and 33.

In document photosensors 10 f, 10 g, 10 h with eight optical elementsshown in FIGS. 8 to 10, upper and lower base plates 13 and 14 aresecured to respectively upper and lower walls 55 a and 55 b to definepassageway 55 in frame 104. Upper and lower brackets 41 and 42 compriserespectively upper and lower partitions 43 and 44 for isolating upperLED and PD chips 21 to 23 and 37, and lower LED and PD chips 31 to 33and 38. Formed in upper and lower substrate 11 and 12 are respectivelyupper and lower openings 11 a and 12 a in which each end of upper andlower partitions 43 and 44 is fit for secure attachment of upper andlower brackets 41 and 42 in position.

In document photosensor 10 f shown in FIG. 8, symmetrically arrangedabout a central point within passageway 55 are respectively first upperand lower LED chips 21 and 31, second upper and lower LED chips 22 and32, third upper and lower LED chips 33, and upper and lower PD chips 37and 38. Turned on at different point in time under time division controlare first to third upper and lower LED chips 21 to 23, 31, 32 and 33 toblock simultaneous receipt of lights from first to third upper and lowerLED chips 21 to 23 and 31 to 33 by upper and lower PD chips 37 and 38.

Upper PD chip 37 receives lights irradiated from first to third lowerLED chips 31 to 33 and then penetrated through bill 50 moving alongpassageway 55, and lower PD chip 38 receives lights irradiated fromfirst to third upper LED chips 21 to 23 and then penetrated through bill50. Light irradiated from first upper LED chip 21 is converted throughupper aspheric lens 51 into parallel light beams which then permeatebill 50 and are received by lower PD chip 38 through lower aspheric lens52. For example, after extinction of first upper LED chip 21, secondupper LED chip 22 is lightened; after extinction of second upper LEDchip 22, third upper LED chip 23 is lightened to detect lights fromfirst to third upper LED chips 21 to 23 by lower PD chip 38 at differenttimes. Also, after extinction of third upper LED chip 23, first lowerLED chip 31 is lightened to emit from lower LED chip 31 light which isthen converted into parallel light beams through lower aspheric lens 52;light beams permeate bill 50 and are received by upper PD chip 37through upper aspheric lens 51. After de-energization of first lower LEDchip 31, second lower LED chip 32 is energized, and afterde-energization of second lower LED chip 32, third lower LED chip 33 isenergized to detect lights from first to third lower LED chips 31 to 33by upper PD chip 37 at different times.

In document photosensor 10 g shown in FIG. 9, symmetrically arrangedabout a central point within passageway 55 are respectively first upperand third lower LED chips 21 and 33, second upper and lower LED chips 22and 32, third upper and first lower LED chips 23 and 31, and upper andlower PD chips 37 and 38. Similarly to document photosensor 10 g of FIG.9, document sensor 10 h of FIG. 10 indicates the symmetrical positionsof first to third upper LED chips 21 to 23 and upper PD chip 37 relativeto first to third lower LED chips 31 to 33 and lower PD chip 38 about acentral transverse axis within passageway 55. However, the arrangementin FIG. 10 is different from that in FIG. 8 because FIG. 8 indicates thestructure wherein upper PD chip 37 and upper partition 43 of upperbracket 41 stand between first and second upper LED chips 21, 22 andthird upper LED chip 23, and likewise, lower PD chip 38 and lowerpartition 44 of lower bracket 42 stand between first and second lowerLED chips 31, 32 and third lower LED chip 33. In document photosensors10 f, 10 g, 10 h shown in FIGS. 8 to 10, a distance of 0.6 mm or lessmay be retained between adjoining LED chips for first to third upper andlower LED chips 21 to 23 and 31 to 33 secured on first and secondsubstrates 11 and 12.

In document photosensors 10 f, 10 g, 10 h with eight optical elementsshown in FIGS. 8 to 10, first to third upper and lower LED chips 21 to23 and 31 to 33 may be lightened with different wavelengths to detectand prepare six kinds of transmitted light pattern data of bill 50 bycontrol device (not shown) electrically connected to upper and lower PDchips 37 and 38 so that control device may compare detected six kinds ofdata with reference benchmarks stored in control device to validateauthenticity of bill 50.

Document photosensor 10 f shown in FIG. 8 has three LED chip pairssymmetrically arranged each other that comprise first upper and lowerLED chips 21 and 31, second upper and lower LED chips 22 and 32, andthird upper and lower LED chips 23 and 33 to produce lights of the samewavelength from paired LED chips. This enables to pick out sametransmitted light pattern data independently of right side up or bottomside up insertion of bill 50 into inlet 101 of bill validator becauselights of same wavelength penetrate and scan substantially the samepositions in bill 50 from upside or downside in mirror image. Forexample, for a baseline level in authenticity decision of bill 50,control device may decide bill 50 as genuine when the resultant lightdata patterns fulfill the following requirements:

1. Each ratio of received and added light amount from first to thirdupper LED chips 21 to 23 to received light amount from any one of firstto third upper LED chips 21 to 23 is within a predetermined range, and

2. Each ratio of received and added light amount from first to thirdlower LED chips 31 to 33 to received light amount from any one of firstto third lower LED chips 31 to 33 is within a predetermined range.

FIGS. 11 and 12 illustrate document photosensors 10 i and 10 j with tenoptical elements according to the present invention. Documentphotosensor 10 i shown in FIG. 11 comprises upper sensor assembly 1disposed on one side of passageway 55 along which bill 50 is transportedand lower sensor assembly 2 disposed on the opposite side of passageway55 from upper sensor assembly 1. Upper sensor assembly 1 comprises upperbase plate 13 having a plurality of upper terminals 63, upper substrate11 disposed on upper base plate 13 and having a plurality of upperconductive leads 61, first to fourth upper LED chips 21 to 24individually surface-mounted on upper substrate 11 and each having apair of terminals electrically connected to related ones of upperconductive leads 61, upper PD chip 37 surface-mounted on upper substrate11 and having a pair of terminals electrically connected to related onesof upper conductive leads 61, upper bracket 41 disposed on uppersubstrate 11, and an upper aspheric lens 51.

As shown in FIG. 13, first to fourth upper LED chips 21 to 24 each haveone terminal individually secured on and electrically connected todiscrete upper emission electrode 71 formed on upper substrate 11; eachupper emission electrode 71 is connected to one of upper leads 61; theother terminals of first to fourth upper LED chips 21 to 24 areindividually electrically connected to different ones of upper leads 61through golden wire. One terminal of upper PD chip 37 is secured on andelectrically connected to upper acceptance electrode 81 formed on uppersubstrate 11; upper acceptance electrode 81 is connected to another oneof upper leads 61; and the other terminal of upper PD chip 37 areelectrically connected to another upper lead 61 through golden wire.Upper emission and acceptance electrodes 71 and 81 are arranged inalignment with first array line 56 perpendicular to longitudinaldirection of passageway 55. A plurality of upper leads 61 on uppersubstrate 11 are electrically connected to upper terminals 63 on uppersubstrate 13 through solder or brazing metal to individually feedelectric power to first to fourth upper LED chips 21 to 24 through upperleads 61. Upper aspheric lens 51 is secured within upper bracket 41opposite to first to fourth upper LED chips 21 to 24 and upper PD chip37.

Just as upper sensor assembly 11 already is, as shown in FIGS. 11 and12, lower sensor assembly 2 comprises a lower base plate 14 having aplurality of lower terminals 64, a lower substrate 12 disposed on lowerbase plate 14 and having a plurality of lower leads 62, first to fourthlower LED chips 31 to 34 individually surface-mounted on lower substrate12 and having a pair of terminals electrically connected to related onesof lower conductive leads 62, a lower PD chip (lower light receivingelement) 38 surface-mounted on lower substrate 12 and having a pair ofterminals electrically connected to related ones of lower conductiveleads 62, a lower bracket 42 disposed on lower substrate 12, and a loweraspheric lens 52 supported on lower bracket 42.

As shown in FIG. 13, first to fourth lower LED chips 31, 32, 33, 34 eachhave one terminal individually secured on and electrically connected todiscrete lower emission electrode 72 formed on lower substrate 12; eachlower emission electrode 72 is connected to one of lower leads 62; theother terminal of first to fourth lower LED chips 31 to 34 isindividually electrically connected to another one of lower leads 62through golden wire. One terminal of lower PD chip 38 is secured on andelectrically connected to lower acceptance electrode 82 formed on lowersubstrate 12; lower acceptance electrode 82 is connected to another oneof lower leads 62; the other terminal of lower PD chip 38 iselectrically connected to another one of lower leads 62 through goldenwire. Lower emission and acceptance electrodes 72 and 81 are arranged inalignment with second array line 57 perpendicular to longitudinaldirection of passageway 55. A plurality of lower leads 62 on lowersubstrate 12 are electrically connected to lower terminals 64 on lowerbase plate 14 via solder or brazing metal to individually provideelectric power to first to fourth lower LED chips 31 to 34 and lower PDchip 38. Lower aspheric lens 52 is secured within lower bracket 42opposite to first to fourth lower LED chips 31 to 34 and lower PD chip38.

Document photosensor 10 i shown in FIG. 11, a pitch distance of 0.6 mmor less may be set between adjoining chips in first to fourth upper andlower LED chips 21 to 24 and 31 to 34. Upper aspheric lens 51 convertsall lights from first to fourth upper LED chips 21 to 24 into parallellight beams of generally rectangular or ellipse section that areprojected onto bill 50 with the light beams of their longitudinalprojective length (in the transverse direction of passageway 55) greaterthan their width length (in the longitudinal direction of passageway 55)so that lower and upper PD chips 38 and 37 may each detect lightpatterns transmitted through substantially same area or mainlyoverlapped area of bill 50 after irradiation from first to fourth upperand lower LED chips 21 to 24 and 31 to 34.

To this end, upper and lower aspheric lenses 51 and 52 may transforminto parallel linear light beams all lights from first to fourth upperand lower LED chips 21 to 24 and 31 to 34. Also, upper and loweraspheric lenses 51 and 52 may operate to converge onto respectivelyupper and lower PD chip 37 and 38 lights from first to fourth lower LEDchips 31 to 34 and first to fourth upper LED chips 21 to 24 after theirtransmission through bill 50 without requirement of providing anyinherent unitized lens in first to fourth upper and lower light emittingelements 21 to 24 and 31 to 34.

Document photosensor 10 i shown in FIG. 11, upper and lower base plates13 and 14 are secured to respectively upper and lower walls 55 a and 55b to define passageway 55 in frame 104. Upper and lower brackets 41 and42 comprise respectively upper and lower partitions 43 and 44 forisolating first to fourth upper LED and PD chips 21 to 24 and 37, andfirst to fourth lower LED and PD chips 31 to 34 and 38. Formed in upperand lower substrate 11 and 12 are respectively upper and lower openings11 a and 12 a in which each end of upper and lower partitions 43 and 44is fit for secure attachment of upper and lower brackets 41 and 42 inposition.

Upper and lower aspheric lenses 51 and 52 are disposed on respectivelyupper and lower partitions 43 and 44 in a spaced relation to first tofourth upper LED chips 21 to 24 and PD chip 37 and to first to fourthlower LED chips 31 to 34 and PD chip 38. Upper partition 43 of upperbracket 41 serves to block direct incidence of light from first tofourth upper LED chips 21 to 24 into upper PD chip 37 adjacent to firstto fourth upper LED chips 21 to 24 to prevent pseudo-lighting ormalfunction of upper PD chip 37. Alike, lower partition 44 of lowerbracket 42 serves to block direct incidence of light from first tofourth lower LED chips 31 to 34 into lower PD chip 38 adjacent to firstto fourth lower LED chips 31 to 34 to prevent pseudo-lighting of lowerPD chip 38.

Lower PD chip 38 has the acceptance surface whose length along secondarray line 57 is equal to or greater than a length along first arrayline 56 of an emission surface in first to fourth upper LED chips 21 to24. Likewise, upper PD chip 37 has the acceptance surface whose lengthalong first array line 56 is equal to or greater than a length alongsecond array line 57 of an emission surface in first to fourth lower LEDchips 31 to 34. This structure ensures receipt of full amount of lightspenetrated through bill 50 by upper and lower PD chips 37 and 38. By wayof example, each length along first and second array lines 56, 57 ofrespective acceptance surface in upper and lower PD chips 37, 38 may beequal to or less than 1.5 mm.

In document photosensor 10 i shown in FIG. 11, upper PD chip 37 isarranged between a pair of first and second upper LED chips 21, 22 and apair of third and fourth upper LED chips 23, 24, and lower PD chip 38 isarranged between a pair of first and second lower LED chips 31, 32 and apair of third and fourth lower LED chips 33, 34. Document photosensor 10i has the axisymmetric structure about Z and X axes passing a centralpoint in passageway 55 regarding first upper and lower LED chips 21, 31,second upper and lower LED chips 22, 32, third upper and lower LED chips23, 33 and fourth upper and lower LED chips 24, 34. First to fourthupper and lower LED chips 21 to 24 and 31 to 34 are turned on atdifferent points in time to block simultaneous receipt of lights fromfirst to fourth upper and lower LED chips 21 to 24 and 31 to 34 by upperand lower PD chips 37 and 38.

After extinction of first upper LED chip 21, second upper LED chip 22 isturned on; after extinction of second upper LED chip 22, third upper LEDchip 23 is turned on; after extinction of third upper LED chip 23,fourth upper LED chip 24 is turned on to detect all lights from first tofourth upper LED chips 21 to 24 by lower PD chip 38. Then, afterextinction of fourth upper LED chip 24, first lower LED chip 31 isturned on to produce a light that is converted through lower asphericlens 52 into parallel light beams that are received by upper PD chip 37through upper aspheric lens 51. After extinction of first lower LED chip31, second lower LED chip 32 is turned on; after extinction of secondlower LED chip 32, third lower LED chip 33 is turned on; afterextinction of third lower LED chip 33, fourth lower LED chip 34 isturned on; all lights from first to fourth lower LED chips 31 to 34 arereceived by upper PD chip 37.

In document photosensor 10 i with ten optical elements shown in FIG. 11,first to fourth upper and lower LED chips 21 to 24 and 31 to 34 may emitlights of different wavelength to detect and prepare eight kinds oftransmitted light pattern data of bill 50 by control device (not shown)electrically connected to upper and lower PD chips 37 and 38 so thatcontrol device may compare detected eight kinds of data with referencebenchmarks stored in control device to validate authenticity of bill 50.

Document photosensor 10 f shown in FIG. 11 has four LED chip pairssymmetrically arranged each other that comprise first upper and lowerLED chips 21 and 31, second upper and lower LED chips 22 and 32, thirdupper and lower LED chips 23 and 33 and four upper and lower LED chips24 and 34 to produce lights of the same wavelength from paired LEDchips. This enables to pick out same transmitted light pattern dataindependently of right side up or bottom side up insertion of bill 50into inlet 101 of bill validator because lights of same wavelengthpenetrate and scan substantially the same positions in bill 50 fromupside or downside in mirror image. For example, for a baseline level inauthenticity decision of bill 50, control device may decide bill 50 asgenuine when the resultant light data patterns fulfill the followingrequirements:

1. Each ratio of received and added light amount from first to fourthupper LED chips 21 to 24 to received light amount from any one of firstto fourth upper LED chips 21 to 24 is within a predetermined range, and

2. Each ratio of received and added light amount from first to fourthlower LED chips 31 to 34 to received light amount from any one of firstto fourth lower LED chips 31 to 34 is within a predetermined range.

In document photosensor 10 j shown in FIG. 12, upper PD chip 37 isarranged between a group of first to third upper LED chips 21 to 23 andfourth upper LED chips 24, and lower PD chip 38 is arranged between agroup of first to third lower LED chips 31 to 33 and fourth lower LEDchip 34. As document photosensor 10 i shown in FIG. 11, documentphotosensor 10 j has the axisymmetric structure about Z axis regardingfirst to fourth upper LED chips 21 to 24 and upper PD chip 37 withrespect to first to fourth lower LED chips 31 to 34 and lower PD chip38. Document photosensors 10 i and 10 j are different from each otherbecause in document photosensor 10 j, upper PD chip 37 and upperpartition 43 of upper bracket 41 separate first to third upper LED chips21 to 23 from fourth upper LED chip 24, and likewise, lower PD chip 38and lower partition 44 of lower bracket 42 separate first to third lowerLED chips 31 to 33 from fourth lower LED chip 34. In documentphotosensor 10 j of FIG. 12, a pitch distance of 1 mm or less,preferably 0.6 mm or less may be set between adjoining chips in first tothird upper and lower LED chips 21 to 23 and 31 to 33.

In document photosensor 10 j with ten optical elements shown in FIG. 12,upper PD chip 37 in a light receiving chamber 58 may receive lights thatare emitted from first to third lower LED chips 31 to 33 and penetratedthrough bill 50 moving along passageway 55 and also that is emitted fromfourth upper LED chip 24 and reflected on bill 50. Likewise, lower PDchip 38 in light receiving chamber 58 may receive lights that areemitted from first to third upper LED chips 21 to 23 and penetratedthrough bill 50 and also that is emitted from fourth lower LED chip 34and reflected on bill 50. As upper PD chip 37 receives lights irradiatedfrom first to third lower LED chips 31 to 33 and penetrated through bill50, and lower PD chip 38 receives lights irradiated from first to thirdupper LED chips 21 to 23 and penetrated through bill 50, control devicemay prepare six kinds of transmitted light pattern data of bill 50 andcompare them with previously stored transmitted light pattern data orbenchmarks to decide validity of bill 50 with high accuracy.

Also, when upper PD chip 37 in light receiving chamber 58 receives lightfrom fourth upper LED chip 24 and reflected on bill 50 and lower PD chip38 in light receiving chamber 58 receives light from fourth lower LEDchip 34 and reflected on bill 50, control device may prepare additionaltwo kinds of reflected light pattern data to distinguish a kind of bill50. When one of first to third upper LED chips 21 to 23 irradiates lightof same wavelength as that of light irradiated from fourth upper LEDchip 24, and one of first to third lower LED chips 31 to 33 irradiateslight of same wavelength as that of light irradiated from fourth lowerLED chip 34, control device can pick out same reflected or transmittedlight pattern data for identification of bill kind and bill validationindependently of right side up or bottom side up insertion of bill 50into inlet 101 of bill validator because lights of same wavelengthpenetrate and scan substantially the same positions in bill 50 fromupside or downside in mirror image.

In document photosensors 10 a to 10 j with four, six, eight and tenoptical elements according to the present invention, first to fourthupper and lower LED chips 21 to 24 and 31 to 34 are light emittingdiodes (LED chips) that irradiate lights of wavelength selected from thegroups of ultraviolet, blue, green, red, near-infrared and infraredrays. Not shown in detail in the drawings, but, each LED chip maycomprise a semiconductor substrate and anode and cathode electrodesformed on upper and bottom surfaces of semiconductor substrate.

As shown in FIG. 13, a cathode (bottom) electrode of each LED chip iselectrically connected to upper and lower emission electrodes 71 and 72of upper and lower substrates 11 and 12 through conductive adhesive suchas solder, and upper and lower emission electrodes 71 and 72 areelectrically connected to respectively upper and lower leads 61 and 62.Anode electrodes (upper electrodes) of LED chips each are electricallyconnected to upper and lower leads 61 and 62 on upper and lowersubstrates 11 and 12 through metallic thin lines or bonding wires suchas golden wires. All embodiments of the present invention contemplatecoverage by light-transmissive protective resin 39 that encapsulateslight-emitting semiconductor diode chips, metallic thin lines, a part offirst and second leads 61 and 62 exposed from first and secondsubstrates 11 and 12 to prevent extrusion of extraneous material such asmoisture into the device from outside for degradation control of LEDchips 21 to 24 and 31 to 34.

Upper and lower PD chips 37 and 38 are photodiodes that each comprise asemiconductor substrate, anode and cathode terminals formed onsemiconductor substrate. Each anode terminal (one terminal) of upper andlower PD chips 37 and 38 are electrically connected to upper and loweracceptance electrodes 81 and 82 on upper and lower substrates 11 and 12,and each cathode terminal (the other terminal) of upper and lower PDchips 37 and 38 are electrically connected to upper and lower leads 61and 62 though metallic thin lines or bonding wires such as golden wires.Like LED chips 21 to 24 and 31 to 34, the present invention contemplatescoverage by light-transmissive protective resin 39 that encapsulatesphotodiode chips, metallic thin lines, a part of first and second leads61 and 62 exposed from first and second substrates 11 and 12 to preventextrusion of extraneous material such as moisture into the device fromoutside for degradation control of LED chips 21 to 24 and 31 to 34. Inlieu of or in addition to photodiodes, substitutes or other opticaldetectors such as phototransistors of emitter, base and collectorterminals may be used.

Known printed circuit boards such as glass epoxy substrate may be usedto prepare upper and lower substrates 11 and 12 and upper and lower baseplates 13 and 14, and a printing machine not shown is used to printsolder paste on upper and lower substrates 11 and 12 to form upper andlower emission electrodes 71 and 72 and upper and lower acceptanceelectrodes 81 and 82. Then, mounters not shown are used to mount firstto fourth upper and lower LED chips 21 to 24 and 31 to 34 and upper andlower PD chips 37 and 38 in solder paste on upper and lower substrates11 and 12 with high accuracy. Then, upper and lower substrates 11 and 12are located in reflow furnace to fasten all chips 21 to 24, 31 to 34, 37and 38 on upper and lower emission electrodes 71 and 72 and upper andlower acceptance electrodes 81 and 82 by heating solder paste.Subsequently, wire bonding technique is used to electrically connectbetween mating electrodes to supply electric power to upper and lowerterminals 63 and 64 from power source not shown of bill validator.

In document photosensors 10 a to 10 j, first to fourth upper lightemitting elements 21 to 24 are arranged on upper substrate 11 inalignment with first array line 56 perpendicular to longitudinaldirection of passageway 55 to locate upper light receiving element 37between first and second upper light emitting elements 21 and 22,between second and third upper light emitting elements 22 and 23 orbetween third and fourth upper light emitting elements 23 and 24.Likewise, first to fourth lower light emitting elements 31 to 34 arearranged on lower substrate 12 in alignment with second array line 57perpendicular to longitudinal direction of passageway 55 to locate lowerlight receiving element 38 between first and second lower light emittingelements 31 and 32, between second and third lower light emittingelements 32 and 33 or between third and fourth lower light emittingelements 33 and 34.

In manufacture, a pitch distance of a few millimeters, in fact 1 mm orless, preferably 0.6 mm or less may be set between adjoining chips infirst to third upper and lower LED chips 21 to 23 and 31 to 33 exactlysurface-mounted on upper and lower substrates 11 and 12 by mounters.This can achieve detection by upper and lower PD chips 37 and 38 oflights irradiated form first to fourth upper and lower LED chips 21 to24 and 31 to 34 and transmitted through substantially same or overlappedarea of bill 50 for improvement in detection accuracy.

Direct attachment of first to fourth upper and lower LED chips 21 to 24and 31 to 34 on upper and lower substrates 11 and 12 is veryadvantageous because it can notably and more reduce the thickness andarray length of document photosensors 10 a to 10 j compared to prior artstructures by pin-insertion technique. Also, this direct attachment canrealize attachment of each LED chips 21 to 24 and 31 to 34 on upper andlower substrates 11 and 12 in exact alignment with their optical axesfor without irregular or deviated attachment of LED chips unlike priorart sensing devices whose plastic shell and extended outer pins maydisadvantageously lead to deviation or misalignment of mounted LED chipsin plastic shells on the order of 150 micrometers when outer pins areattached in through-holes. However, the present invention may controldeviation or misalignment below a few micrometers in mounting first tofourth upper and lower LED chips 21 to 24 and 31 to 34 on upper andlower substrates 11 and 12.

Now, as shown in FIG. 14, document photosensors may be assembled bymounting in turn respectively upper and lower substrates 11, 12, upperand lower brackets 41, 42, upper and lower aspheric lenses 51, 52 overupper and lower base plates 13, 14. Upper and lower brackets 41, 42 areformed from opaque or light-impermeable plastic material selected fromthe group of epoxy resin, ABS resin, polycarbonate resin, polyamideresin, polyacetal resin, polypropylene and acrylic resin. Upper andlower aspheric lenses 51, 52 are formed from transparent orlight-permeable plastic material such as polycarbonate resin or acrylicresin.

As shown in FIG. 15, flexible sealing members 46 are attached to orintegrally formed with a bottom portion of upper and lower brackets 41,42 to bring flexible sealing members 46 into close contact to a surfaceof upper and lower substrates 11, 12 when upper and lower brackets 41,42 are mounted on upper and lower substrates 11, 12. For example, upperand lower brackets 41, 42 are formed of relatively hard plastics such asepoxy resin, and sealing members 46 are formed of relatively softelastomer such as silicone resin along bottoms of and integrally withupper and lower brackets 41, 42 so that sealing members 46 may slightlydeform along edges 11 b, 12 b of upper and lower substrates 11, 12 whensealing members 46 are brought into contact to edges 11 b, 12 b. Sealingmembers 46 ensures firm sealing between upper and lower brackets 41, 42and upper and lower substrates 11, 12 to prevent incidence of ambientlights and invasion of extraneous substance into upper and lowerbrackets 41, 42 that may deteriorate detection accuracy for upper andlower sensor assemblies 1, 2. Sealing members 46 also serve to firmlysupport mechanically structural elements in assemblies.

As is apparent from FIG. 14, each of upper and lower aspheric lenses 51,52 has the generally pentagonal section made up of a round tip 51 d, 52d for forming cylindrical or curved surface, and two tapered surfaces 51a, 52 a converging toward round tip 51 a, 52 a. Formed at upper portionsof upper and lower partitions 43, 44 in upper and lower brackets 41, 42are notches with two tapered surfaces 43 a, 44 a of the shapecomplementary to tapered surfaces 51 a, 52 a of aspheric lenses 51, 52.As shown in FIG. 15, when upper and lower aspheric lenses 51, 52 areattached on upper and lower brackets 41, 42, tapered surfaces 51 a, 52 aof aspheric lenses 51, 52 are appropriately fit on two tapered surfaces43 a, 44 a of partitions 43, 44 for their secure support. Preferably,tapered surfaces 51 a, 52 a may have an angle in an angular rangebetween 60 and 120 degrees, in particular of 90 degrees to properlyconvert lights from first to fourth upper and lower LED chips 21 to 24and 31 to 34 into parallel light beams toward bill 50. Upper and loweraspheric lenses 51, 52 have plane surfaces 51 b, 52 b opposite totapered surfaces 51 a, 52 a to irradiate lights of generally rectangularsection from plane surfaces 51 b, 52 b.

As shown in FIGS. 11 and 12, each length along X axis of upper and loweraspheric lenses 51, 52 is longer than each array length of first tofourth upper LED chips 21 to 24 and upper PD chip 37 and first to fourthlower LED chips 31 to 34 and lower PD chip 38, both aspheric lenses 51,52 are arranged in a line along X axis to positively irradiate lightsfrom first to fourth upper and lower LED chips 21 to 24 and 31 to 34onto upper and lower PD chips 37, 38 while penetrating upper and loweraspheric lenses 51, 52 and bill 50.

Upper and lower aspheric lenses 51, 52 each have their elongatedlongitudinal length perpendicular to longitudinal direction ofpassageway 55 to widen, along elongated longitudinal length of asphericlenses 51, 52, light beams irradiated from plane surfaces 51 b, 52 b ofaspheric lenses 51, 52. Whereas prior art shell-shaped LEDs irradiatelights of generally circular section onto bill, document photosensors 10according to these embodiments may irradiate light beams of generallyrectangular section onto bill 50 through upper and lower aspheric lenses51, 52 to pick out transmitted light data through a wider range of bill50. As shown in FIG. 16, steps 51 c, 52 c may be formed between planesurfaces 51 b, 52 b and tapered surface 51 a, 52 a of upper and loweraspheric lenses 51, 52 to reduce areas of plane surfaces 51 b, 52 b forthe purpose of confining a light irradiation area on bill 50 anddetecting transmitted light data of a narrower area in bill 50.

Document photosensors of the invention may have four, six, eight or tenoptical elements of same or different structures apposed along X axis.In fact, document photosensors shown in FIGS. 17 to 21 utilizeultraviolet, blue, green, red, near infrared and infrared rays LED chipsUV, B, G, R NIR and IR of respectively their wavelengths on the order of370, 470, 525, 620, 740 and 830 nm.

An embodiment of the sensor device 20 a shown in FIG. 17 comprises acentral document photosensor 30 a with four optical elements, two rightand left side document photosensors 30 b, 30 c each with four opticalelements on either side of central document photosensor 30 a alldisposed in a line along X axis. Central document photosensor 30 acomprises first upper and lower LED chips 21, 31 disposed as in documentphotosensor 10 a shown in FIG. 1. Right side document photosensor 30 bcomprises first upper and lower LED chips 21, 31 disposed as in documentphotosensor 10 b shown in FIG. 3. Left side document photosensor 30 chas an inverted structure of right side document photosensor 30 b aboutcentral document photsensor 30 a wherein each chip is disposed in asymmetric position regarding first upper and lower LED chips 21, 31 andupper and lower PD chips 37, 38 in document photosensor shown in FIG. 3.

First upper and lower LED chips 21, 31 in each document photosensors 30a, 30 b, 30 c are turned on at different points in time under timedivision control. Also, although upper and lower LED chips 21, 31 areturned on at a time, upper and lower partitions 43, 44 for separatingbetween adjoining document photosensors 30 a, 30 b, 30 c effectivelyprevent simultaneous detection of plural light by upper and lower PDchips 37, 38.

Upper and lower LED chips 21, 31 produce lights of bilaterallysymmetrical wavelength about a central vertical axis 29 of centraldocument photosensor 30 a. This LED chip array enables to pick out sametransmitted light pattern data independently of right side up or bottomside up insertion of bill 50 into inlet 101 of bill validator becauselights of same wavelength penetrate and scan substantially the samepositions in bill 50 from upside or downside in mirror image. Forexample, if inverted bill 50 is inserted into passageway 55, lights ofsame wavelength are irradiated onto bill 50 from the upper and lowersides.

Control device decides an amount of a first light irradiated from firstupper LED chip 21 in upper sensor assembly 1, penetrated through bill 50and received by lower PD chip 38. Control device also decides an amountof a second light irradiated from first lower LED chip 31 in lowersensor assembly 2, penetrated through bill 50 and received by upper PDchip 37. In addition, when received amount of first and second lights isin a predetermined rage range, control device decides bill 50 as genuineto drive conveyer device to transmit bill 50 to a stacking chamber.

In the sensor device 20 a shown in FIG. 17, right and left side documentphotosensors 30 b, 30 c on the opposite sides of central photosensor 30a in a line are used to decide a kind of bill 50. When first upper andlower LED chips 21, 31 in right and left side document photosensors 30b, 30 c irradiate first and second lights which are reflected on bill 50and received by upper and lower PD chips 37, 38 in light receivingchamber 58, control device may compare amount of first and second lightsreceived by upper and lower PD chips 37, 38 with stored one to decide akind of inserted bill 50.

Another embodiment of the sensor device 20 b shown in FIG. 18 comprisesa central document photosensor 30 a with six optical elements, two rightand left side document photosensors 30 b, 30 c each with six opticalelements on either side of central document photosensor 30 a alldisposed in a line along X axis. Central document photosensor 30 acomprises first and second upper and lower LED chips 21, 22, 31, 32disposed as in document photosensor 10 c shown in FIG. 5. Right sidedocument photosensor 30 b comprises first and second upper and lower LEDchips 21, 22, 31, 32 disposed as in document photosensor 10 b shown inFIG. 6. Left side document photosensor 30 c has an inverted structure ofright side document photosensor 30 b about central document photsensor30 a wherein each chip is disposed in a symmetric position regardingfirst and second upper and lower LED chips 21, 22, 31, 32 and upper andlower PD chips 37, 38 in document photosensor 10 b shown in FIG. 6.

First and second upper and lower LED chips 21, 22, 31, 32 in eachdocument photosensor 30 a, 30 b, 30 c are turned on at different pointsin time. Also, although LED chips 21, 22, 31, 32 in each documentphotosensor 30 a, 30 b, 30 c are turned on at a time, upper and lowerpartitions 43, 44 for separating between adjoining document photosensors30 a, 30 b, 30 c effectively prevent simultaneous detection of plurallight by upper and lower PD chips 37, 38.

Upper and lower LED chips 21, 22, 31, 32 produce lights of bilaterallysymmetrical wavelength about a central vertical axis 29 of centraldocument photosensor 30 a. This LED chip array enables to pick out sametransmitted light pattern data independently of right side up or bottomside up insertion of bill 50 into passageway 55 of bill validatorbecause lights of same wavelength penetrate and scan substantially thesame positions in bill 50 from upside or downside in mirror image. Forexample, if inverted bill 50 is inserted into passageway 55, lights ofsame wavelength are irradiated onto bill 50 from the upper and lowersides.

Control device decides a total amount of received lights by addingamounts of first and second lights that are irradiated from first andsecond upper LED chips 21, 22, penetrated through bill 50 and receivedby lower PD chip 38. Then, control device calculates ratio of receivedamounts of first and second lights to the total amount, and decides bill50 as genuine when each quotient is within a predetermined range.

As in upper sensor assembly 1, in lower sensor assembly 2, controldevice decides a total amount of received lights by adding amounts ofthird and fourth lights that are irradiated from first and second lowerLED chips 31, 32, penetrated through bill 50 and received by upper PDchip 37. Then, control device calculates ratio of received amounts ofthird and fourth lights to the total amount, and decides bill 50 asgenuine when each quotient is within a predetermined range. In this way,control device decides bill 50 as genuine when ratio of received amountof first to fourth lights to total amount is within a predeterminedrange to transmit bill 50 to a stacking chamber.

In the sensor device 20 b shown in FIG. 18, right and left side documentphotosensors 30 b, 30 c on the opposite sides of central documentphotosensor 30 a in a line are used to decide a kind of bill 50. Whensecond upper and lower LED chips 22, 32 in right and left side documentphotosensors 30 b, 30 c irradiate second and fourth lights which arereflected on bill 50 and received by upper and lower PD chips 37, 38 inlight receiving chamber 58.

Still another embodiment of the sensor device 20 c shown in FIG. 19comprises a central document photosensor 30 a with eight opticalelements, two right and left side document photosensors 30 b, 30 c eachwith eight optical elements on either side of central documentphotosensor 30 a all disposed in a line along X axis. Central documentphotosensor 30 a comprises first to third upper and lower LED chips 21to 23 and 31 to 33 disposed as in document photosensor 10 g shown inFIG. 9. Right side document photosensor 30 b comprises first to thirdupper and lower LED chips 21 to 23 and 31 to 33 disposed as in documentphotosensor 10 f shown in FIG. 8. Left side document photosensor 30 chas an inverted structure of right side document photosensor 30 b aboutcentral document photsensor 30 a wherein each chip is disposed in asymmetric position regarding first and second upper and lower LED chips21 to 23, 31 to 33 and upper and lower PD chips 37, 38 in documentphotosensor 10 f shown in FIG. 8.

First to third upper and lower LED chips 21 to 23 and 31 to 33 in eachdocument photosensor 30 a, 30 b, 30 c are turned on at different pointsin time. Also, although LED chips 21 to 23 and 31 to 33 in each documentphotosensor 30 a, 30 b, 30 c are turned on at a time, upper and lowerpartitions 43, 44 for separating between adjoining document photosensors30 a, 30 b, 30 c effectively prevent simultaneous detection of plurallight by upper and lower PD chips 37, 38.

Upper and lower LED chips 21 to 23 and 31 to 33 produce lights ofbilaterally symmetrical wavelength about a central vertical axis 29 ofcentral document photosensor 30 a. This LED chip array enables to pickout same transmitted light pattern data independently of right side upor bottom side up insertion of bill 50 into passageway 55 of billvalidator because lights of same wavelength penetrate and scansubstantially the same positions in bill 50 from upside or downside inmirror image. For example, if inverted bill 50 is inserted intopassageway 55, lights of same wavelength are irradiated onto bill 50from the upper and lower sides.

Control device decides a total amount of received lights by addingamounts of first and second lights that are irradiated from first andsecond upper LED chips 21, 22, penetrated through bill 50 and receivedby upper PD chip 37. Then, control device calculates ratio of receivedamounts of first and second lights to the total amount, and decides bill50 as genuine when each quotient is within a predetermined range.

As in upper sensor assembly 1, in lower sensor assembly 2, controldevice decides a total amount of received lights by adding amounts ofthird and fourth lights that are irradiated from first and second lowerLED chips 31, 32, penetrated through bill 50 and received by upper PDchip 37. Then, control device calculates ratio of received amounts ofthird and fourth lights to the total amount, and decides bill 50 asgenuine when each quotient is within a predetermined range. In this way,control device decides bill 50 as genuine when ratio of received amountof first to fourth lights to total amount is within a predeterminedrange to transmit bill 50 to a stacking chamber.

In the sensor device 20 c shown in FIG. 19, when third upper and lowerLED chips 23, 33 in right and left side document photosensors 30 b, 30 cirradiate fifth and sixth lights which are reflected on bill 50 andreceived by upper and lower PD chips 37, 38 in light receiving chamber58, control device may compare amount of fifth and sixth lights receivedby upper and lower PD chips 37, 38 with predetermined levels to decide akind of inserted bill 50.

A further embodiment of the sensor device 20 d shown in FIG. 20comprises a central document photosensor 30 a with ten optical elements,two right and left side document photosensors 30 b, 30 c each with tenoptical elements on either side of central document photosensor 30 a alldisposed in a line along X axis. Central document photosensor 30 acomprises first to fourth upper and lower LED chips 21 to 24 and 31 to34 disposed as in document photosensor 10 i shown in FIG. 11. Right sidedocument photosensor 30 b comprises first to fourth upper and lower LEDchips 21 to 24 and 31 to 34 disposed as in document photosensor 10 jshown in FIG. 12. Left side document photosensor 30 c has an invertedstructure of right side document photosensor 30 b about central documentphotsensor 30 a wherein each chip is disposed in a symmetric positionregarding first to fourth upper and lower LED chips 21 to 24, 31 to 34and upper and lower PD chips 37, 38 in document photosensor 10 j shownin FIG. 12.

First to fourth upper and lower LED chips 21 to 24 and 31 to 34 in eachdocument photosensor 30 a, 30 b, 30 c are turned on at different pointsin time. Also, although LED chips 21 to 24 and 31 to 34 in each documentphotosensor 30 a, 30 b, 30 c are turned on at a time, upper and lowerpartitions 43, 44 for separating between adjoining document photosensors30 a, 30 b, 30 c effectively prevent simultaneous detection of plurallight by upper and lower PD chips 37, 38.

Upper and lower LED chips 21 to 24 and 31 to 34 produce lights ofbilaterally symmetrical wavelength about a central vertical axis 29 ofcentral document photosensor 30 a. This LED chip array enables to pickout same transmitted light pattern data independently of right side upor bottom side up insertion of bill 50 into passageway 55 of billvalidator because lights of same wavelength penetrate and scansubstantially the same positions in bill 50 from upside or downside inmirror image. For example, if inverted bill 50 is inserted intopassageway 55, lights of same wavelength are irradiated onto bill 50from the upper and lower sides.

The sensor device 20 d shown in FIG. 20 is advantageous in comparingprior art optical sensor device 111 shown in FIG. 22 because sensordevice 20 d may improve validation performance with increased number ofLED chips capable of radiating lights of different wavelength and alsoreduce number of expensive PD chips to cut down on cost for manufacture.Control device decides a total amount of received lights by addingamounts of first to third lights that are irradiated from first to thirdupper LED chips 21 to 23 penetrated through bill 50 and received bylower PD chip 38. Then, control device calculates ratio of receivedamounts of first to third lights to the total amount, and decides bill50 as genuine when each quotient is within a predetermined range.

As in upper sensor assembly 1, in lower sensor assembly 2, controldevice decides a total amount of received lights by adding amounts offourth to sixth lights that are irradiated from first and second lowerLED chips 31 to 33, penetrated through bill 50 and received by upper PDchip 37. Then, control device calculates ratio of received amounts offourth to sixth lights to the total amount, and decides bill 50 asgenuine when each quotient is within a predetermined range. In this way,control device decides bill 50 as genuine when ratio of received amountof first to sixth lights to total amount is within a predetermined rangeto transmit bill 50 to a stacking chamber.

In the sensor device 20 d shown in FIG. 20, when fourth upper and lowerLED chips 24, 34 irradiate seventh and eighth lights which are reflectedon bill 50 and received by upper and lower PD chips 37, 38, controldevice may compare amount of seventh and eighth lights received by upperand lower PD chips 37, 38 with predetermined levels to decide a kind ofinserted bill 50.

The sensor device may comprise any combination of optical elementsselected from the group of four, six, eight and ten optical elementsapposed along X axis. A still further embodiment of the sensor device 20e shown in FIG. 21 comprises a central document photosensor 40 a withsix optical elements, two right central and end document photosensors 40b, 40 c with respectively eight and ten optical elements, and two leftcentral and end document photosensors 40 d, 40 e with respectively eightand ten optical elements all disposed in a line along X axis.

Central document photosensor 40 a comprises first to fourth upper andlower LED chips 21, 22 and 31, 32 disposed as in document photosensor 10d shown in FIG. 6. Right central document photosensor 40 b comprisesfirst to third upper and lower LED chips 21 to 23 and 31 to 33 disposedas in document photosensor 10 f shown in FIG. 8. Right end documentphotosensor 40 c comprises first to fourth upper and lower LED chips 21to 24 and 31 to 34 disposed as in document photosensor 10 j shown inFIG. 12. Left central document photosensor 40 d has an invertedstructure of right central document photosensor 40 b about centraldocument photsensor 40 a wherein each chip is disposed in a symmetricposition regarding first to third upper and lower LED chips 21 to 23, 31to 33 and upper and lower PD chips 37, 38 in document photosensor 10 fshown in FIG. 8. Left end document photosensor 40 e has an invertedstructure of right end document photosensor 40 c about central documentphotosensor 40 a wherein each chip is disposed in a symmetric positionregarding first to fourth upper and lower LED chips 21 to 24, 31 to 34and upper and lower PD chips 37, 38 in document photosensor 10 j shownin FIG. 12.

Upper and lower LED chips 21 to 24 and 31 to 34 produce lights ofbilaterally symmetrical wavelength about a central vertical axis 29 ofcentral document photosensor 40 a. This LED chip array enables to pickout same transmitted light pattern data independently of right side upor bottom side up insertion of bill 50 into passageway 55 of billvalidator because lights of same wavelength penetrate and scansubstantially the same positions in bill 50 from upside or downside inmirror image. For example, if inverted bill 50 is inserted intopassageway 55, lights of same wavelength are irradiated onto bill 50from the upper and lower sides. In sensor device 20 e shown in FIG. 21,fourth upper and lower LED chips 24, 34 in right and left end documentphotosensors 40 c, 40 e irradiate lights that are reflected on bill 50to utilize these lights for decision on kind of bill, and all otherlights may be used to validate bill 50 that are irradiated from LEDchips 21 to 23 and 31 to 33 and penetrated through bill 50.

Light data of lights transmitted through bill 50 is used to detect forexample each quality in ink on front and back surfaces, paper qualityand thickness of bill 50, and so, bill validators for discriminatinghighly counterfeited notes typically utilize transmitted light datarather than reflected light data of bills. Also, it is possible todetect three or more kinds of transmitted light data from a same area ofbill 50 and validate elaborately forged notes with high accuracy.However, data of lights reflected on bill 50 may be used for validationby detecting by lower and upper PD chips 38 and 37 lights irradiatedfrom first to third upper and lower LED chips 21 to 23 and 31 to 33 andreflected on bill 50. Alternatively, authenticity of bill 50 may bedecided by detecting by lower and upper PD chips 38 and 37 in lightreceiving chamber 58 lights irradiated from fourth upper and lower PDchips 38 and 37 lights irradiated from fourth upper and lower LED chips24 and 34 and penetrated through bill 50. Moreover, kind of bill 50 maybe identified by detecting lights radiated from first to fourth upperand lower LED chips 21 to 24 and 31 to 34 and penetrated through bill50.

During transportation through passageway 55 of bill 50 inserted intoinlet 101 of bill validator, it is brought nearly into alignment with alongitudinal central line of or into contact to side walls of passageway55 by means of a centralizing device not shown. In this way, as bill 50is moved along longitudinal central line of passageway 55 and inalignment with each longitudinal line of the above-mentioned documentphotosensors 10 a to 10 j and sensor devices 20 a to 20 e, lightsreleased from LED chips 21 to 24 and 31 to 34 are always irradiated ontosubstantially the same areas of bill 50 in width. Accordingly, inembodiments of document photosensors 10 a to 10 j and sensor devices 20a to 20 e with LED chips symmetrically arranged each other forgenerating lights of same wavelength, they can pick out same transmittedlight pattern data independently of right side up or bottom side upinsertion of bill 50 into passageway 55 of bill validator because lightsof same wavelength penetrate and scan substantially the same positionsin bill 50 from upside or downside in mirror image.

To achieve a modern bill validation for detecting multi-coloredtransmitted light data from a number of microscopic regions of bill toaccurately determine on whether differences or ratios between lights ofdifferent wavelength are within a predetermined reference range, billvalidators need to have surface-mounted light emitting and receivingelements. In this case, LED chips are mounted on same or adjoiningdiscrete support electrodes or terminals on a substrate to cover theseLED chips together or at once with a same protective resin. When LEDchips are mounted on a same electrode on substrate to connect each anodeor cathode electrode of LED chips to a same support electrode, ametallic line (bonding wire) may be used that connects each cathode oranode electrode of LED chips to a discrete or same support electrode onsubstrate. Protective resin for use in surface mounting does not performlight-converging or diverging action without pseudo-lighting of an LEDchip even when an adjoining LED chip is turned on. Pitch distancebetween adjoining LED chips may be 1 mm or less, preferably 0.6 mm orless to perfectly diffuse, disperse or scatter lights of differentwavelength irradiated from LED chips within a diffusion chamber, andthen lights are irradiated as linear light beams onto essentially thesame areas of bill through aspheric lenses to detect them by PD chipsthereby resulting in multi-colored light data from the same areas ofbill. These arrangement and diffusion chamber are free from plastic andlight-focusing encapsulants for sealing LED chips and outer leadsextended from encapsulants.

In embodiments of the present invention shown in FIGS. 6 through 12,first and second light emitting elements 21, 22 each having twoterminals are surface-mounted on same or different emission electrodes71 on substrate 11, and a diffusion chamber 53 is formed between firstand second light emitting elements 21, 22 and aspheric lens 51. Lightemitting elements 21, 22 are coated together with a samelight-transmissive or -permeable protective resin. Light receivingelement 37 having two terminals is surface-mounted on acceptanceelectrode 81 of substrate 11 to gather lights on light receiving element37 through aspheric lenses 51, 52. Otherwise, acceptance electrode 81may be formed on another substrate 12 disposed opposite to substrate 11to surface-mount on acceptance electrode 81 light receiving element 37having two terminals. First and second light emitting elements 21, 22may be surface-mounted on same or different adjoining discrete emissionelectrodes 71 in a spaced relation to each other on substrate 11 by apitch distance of 1 mm or less, preferably 0.6 mm or less.

When first and second LED chips 21, 22 are turned on, lights are emittedfrom their PN junction in the radial direction, and after diffusedwithin diffusion chamber 53, lights are projected on document 50 aftertransmission through aspheric lens 51. Lights are converted throughaspheric lens 51 into linear light beams of generally rectangular orellipse section to compensate difference in actually mounted positionsof first and second LED chips 21, 22 so that a same effect may beobtained as in the case first and second LED chips 21, 22 are on thesame position of substrate 11. Lights reflected on document 50 may bedetected by PD chip 37 in light receiving chamber 58 through asphericlens 51. Lights irradiated from first and second LED chips 21, 22 passthrough diffusion chamber 53 without plastic deterioration by lightirradiation as in shell-shaped LEDs.

Reflective surfaces 54 (FIG. 6) may be formed in brackets 41, 42 forsurrounding first and second LED chips 21, 22 to reflect lightstherefrom toward aspheric lenses 51, 52, and therefore reflectivesurfaces 54 may define a part of diffusion chamber 53. As shown bydotted lines in FIG. 6, reflective surfaces 54 are inclined or tapered,increasing section area of diffusion chamber from first and second LEDchips 21, 22 toward aspheric lens 52. Reflective surfaces 54 are formedinto frustro-etrosa shape such as frustro-conical or -pyramid shape toeffectively increase the amount of reflected lights on brackets 41, 42toward PD chips 37, 38.

The foregoing embodiments of the prevent invention may be modified invarious ways. For example, light data reflected on bill 50 may becollected by means of upper and lower first to third LED chips 21 to 23and 31 to 33 in four, six and eight optical elements. Sensor assembliesmay comprise six or more optical elements with increased number of LEDchips, and may comprise more than two PD chips.

First to fourth upper and lower LED chips 21 to 24 and 31 to 34 may bedisposed in two or more rows perpendicular to longitudinal direction ofpassageway 55. In this case, third and fourth or more array line may beset in parallel to first and second array lines 56, 57. Five or more LEDchips and PD chips may be provided in respectively sensor devices 1, 2.Five or less upper and lower sensor assemblies 1 and 2 are desirable,however, the number of sensor assemblies does not limit the presentinvention. Upper and lower sensor assemblies of same number maypreferably be arranged in alignment with first and second array lines56, 57, however, this structure does not mean any limitation to thepresent invention.

In the shown embodiments, first and second array lines 56, 57 are set inparallel to passageway 55 of bill 55, however, a plane including firstand second array lines 56, 57 may be set perpendicularly to or on aslant at an angle less than 45 degrees.

APPLICABILITY IN INDUSTRY

The present invention is widely applicable to optical sensors for use indocument photosensors such as bill handling apparatuses, billvalidators, bill discriminators and coupon acceptors.

The following enumerates the embodiments according to the presentinvention:

(1) The document photosensor of claim 1, further comprising a sensorassembly (1, 2) disposed on one side of a passageway (55) along which adocument (50) is transported,

wherein the sensor assembly (1, 2) has the substrate (11, 12),

(2) The document photosensor of claim 1, wherein the partition (43, 44)of the bracket (41) is fit in an opening (11 a) formed in the substrate(11, 12).

(3) The document photosensor of the above (1), wherein the sensorassembly (1, 2) is mounted on a base plate (13, 14) with conductiveleads (61) electrically connected to a plurality of upper terminals (63)formed on the base plate (13, 14).

(4) The document photosensor of claim 1, wherein the substrate (11, 12)has an upper substrate (11) disposed on one side of a passageway (55)along which a document (50) is transported and a lower substrate (12)disposed on the opposite side of the passageway (55) from the uppersubstrate (11),

the bracket (41, 42) has an upper bracket (41) disposed on the uppersubstrate (11) for forming an upper light diffusion chamber (53) and anupper light receiving chamber (58) separated from each other, and alower bracket (42) disposed on the lower substrate (12) for forming alower light diffusion chamber (53) and a lower light receiving chamber(58) separated from each other,

the light emitting element (21, 31) has an upper light emitting element(21) surface-mounted on the upper substrate (11) in the upper lightdiffusion chamber (53), and a lower light emitting element (31)surface-mounted on the lower substrate (12) in the lower light diffusionchamber (53),

the light receiving element (37, 38) has an upper light receivingelement (37) surface-mounted on the upper substrate (11) in the upperlight receiving chamber (58) and a lower light receiving element (38)surface-mounted on the lower substrate (12) in the lower light receivingchamber (58).

(5) The document photosensor of the above (4) further comprising: anupper aspheric lens (51) disposed in a spaced relation by a certaindistance to the upper light emitting and receiving elements (21, 37),and

a lower aspheric lens (52) disposed in a spaced relation by a certaindistance to the lower light emitting and receiving element (31, 38).

(6) The document photosensor of claim 4, wherein the bracket (41, 42)comprises a reflective wall (54) in the light diffusion chamber (53),

the reflective wall (54) has an inclined surface with the increasingsection area toward the outside from the light emitting element (21,22).

(7) The document photosensor of claim 1, further comprising alight-transmissive protective resin of same material for covering thelight emitting element (21, 22).

1-15. (canceled)
 16. A document photosensor comprising: a substrate, abracket disposed on the substrate for forming a light diffusion chamberand a light receiving chamber separated from each other, a lightemitting element surface-mounted on the substrate in the light diffusionchamber, and a light receiving element surface-mounted on the substratein the light receiving chamber.
 17. The document photosensor of claim16, wherein a light emitted from the light emitting element passes thelight diffusion chamber, is reflected on a document moved along apassageway, and then is received by the light receiving element in thelight receiving chamber.
 18. The document photosensor of claim 16,wherein the light emitting element has one terminal secured on andelectrically connected to an emission electrode formed on the substrate,the light receiving element has one terminal secured on and electricallyconnected to an acceptance electrode, the emission electrode andacceptance electrode are deployed in alignment on an array lineperpendicular to a moved direction of the document in the passageway.19. The document photosensor of claim 16, further comprising an asphericlens supported on the bracket opposite to the light emitting andreceiving elements.
 20. The document photosensor of claim 19, wherein alight emitted from the light emitting element passes the light diffusionchamber and aspheric lens, is reflected on a document moved along apassageway, passes the aspheric lens and then is received by the lightreceiving element in the light receiving chamber.
 21. A documentphotosensor comprising: a substrate, a bracket disposed on the substratefor forming a light diffusion chamber and a light receiving chamberseparately from each other, first and second light emitting elementssurface-mounted on the substrate in the light diffusion chamber, and alight receiving element surface-mounted on the substrate in the lightreceiving chamber.
 22. The document photosensor of claim 21, whereinlights emitted from the first and second light emitting elements passthe light diffusion chamber, are reflected on a document moved along apassageway, and then are received by the light receiving element in thelight receiving chamber.
 23. The document photosensor of claim 21,further comprising an aspheric lens supported on the bracket opposite tothe first and second light emitting elements and light receivingelement.
 24. The document photosensor of claim 23, wherein lightsemitted from the first and second light emitting elements pass the lightdiffusion chamber and aspheric lens, are reflected on a document, passthe aspheric lens and then are received by the light receiving elementin the light receiving chamber.
 25. The document photosensor of claim21, wherein a distance between the first and second light emittingelements are equal to or less than 0.6 mm.
 26. A document photosensorcomprising: a substrate, a bracket disposed on the substrate for forminga light diffusion chamber and a light receiving chamber separately fromeach other, first, second and third light emitting elementssurface-mounted on the substrate in the light diffusion chamber, and alight receiving element surface-mounted on the substrate in the lightreceiving chamber.
 27. The document photosensor of claim 26, whereinlights emitted from the first, second and third light emitting elementspass the light diffusion chamber, are reflected on a document movedalong a passageway, and then are received by the light receiving elementin the light receiving chamber.
 28. The document photosensor of claim26, further comprising an aspheric lens supported on the bracketopposite to the first, second land third light emitting elements andlight receiving element.
 29. The document photosensor of claim 28,wherein lights emitted from the first, second and third light emittingelements pass the light diffusion chamber, are reflected on a documentmoved along a passageway, and then are received by the light receivingelement in the light receiving chamber.
 30. The document photosensor ofclaim 16, 21 or 26, wherein the bracket has a partition for isolatingbetween the light diffusion chamber and the light receiving chamber.